The present invention relates to compression devices in general, and more particularly, to an inflatable/deflatable cuff or sleeve for simulating blood circulation in the limbs of patients.
The use of cycling pressure applied to the limbs of a patient is old in the art. Representative examples of such cuffs or sleeves are shown in U.S. Pat. No. 3,391,692 issued Jul. 9, 1968 to T. E. Spielberg for "Variable Pressure Casing And Method Of Using For Therapeutic Purposes" and U.S. Pat. No. 3,901,221 issued Aug. 26, 1975 to James E. Nicholson, et al for "Pressure Cycle For Stimulating Blood Circulation In The Limbs". Other example of such devices are found in U.S. Class 128, Subclass 24R.
The compression devices work on a cyclical application of positive and negative fluid pressure to a cuff or sleeve which has at least one fluid chamber. The fluid chamber is connected to a source of fliud that is under alternating relative positive and negative pressures so that a cyclical inflation/deflation sequence is established in the pressure cuff or sleeve. The alternating inflation and deflation cycles provide a stimulation of the blood in the limb positioned within the cuff or sleeve. Typical fluid pressures in the cuff or sleeve range in the order of 40-45 millimeters of mercury (mmHg).
If the sorce of cyclical positive and negative fluid pressures fails to apply negative pressure at the end of an inflation cycle so that the cuff or sleeve remains inflated, the inflated cuff or sleeve produces a deleterious effect upon the patient.
It is, accordingly, a general object of the invention to provide a safety device for inflatable/deflatable pressure cuffs or sleeves.
It is a specific object of the invention to provide a safety pressure release that operates automatically in the event that the cuff or sleeve does not enter into the deflation portion of its cycle.
It is a feature of the invention that the compression cuff or sleeve with the safety device can be used with existing fluid pressure systems.